Nuclear fission power

Reactors, their fuel and the new small and advanced designs.

China leads nuclear fission power research, with 43.3% of the 10% most cited papers published 2021–2025; the United States is second with 22.1%.

Added 14 October 2026. Its top papers were checked for relevance by AI, but its keywords and topic list have not yet been reviewed by hand.

FirstChina43.3%

SecondUnited States22.1%

2.0×lead, by share of the 10% most cited papers, 2021–2025

Highlight a country

Standings

1CNChina43.3%2USUnited States22.1%3KRSouth Korea4.4%4–5GBUnited Kingdom3.1%4–5RURussia3.1%6–7FRFrance2.1%6–7CACanada2.1%8INIndia1.8%9DEGermany1.6%10ITItaly1.4%

Share of the 10% most cited papers, 2021–2025; 748 papers. Source: OpenAlex, pulled 18 October 2026. Method

Year by year

Share of the 10% most cited papers published in each year. Source: OpenAlex, pulled 18 October 2026. Method

Inside the field

Always the top 10%Pilot

Each paper sorted into one sub-area by an AI model reading its title and abstract, then credited as usual. On 200 hand-labelled papers it chose the same sub-area, or a defensible second, 92% of the time.

Sub-area	Papers	First	Second	Third
Actinide separation and radionuclide capture	94	CNChina50.0%	USUnited States11.0%	GBUnited Kingdom9.6%
Molten-salt and liquid-metal coolants and corrosion	93	CNChina44.9%	USUnited States35.3%	CACanada3.7%
Reactor physics, simulation, nuclear data and digital twins	86	CNChina36.7%	USUnited States33.1%	ITItaly2.5%
Thermal hydraulics and boiling heat transfer	78	CNChina63.3%	USUnited States15.7%	KRSouth Korea5.1%
Nuclear fuel materials and performance modelling	74	USUnited States32.0%	CNChina30.2%	FRFrance6.3%
Small modular, micro and space reactors	71	CNChina41.1%	USUnited States15.5%	KRSouth Korea11.3%
Fuel cladding and accident-tolerant fuels	66	CNChina46.8%	USUnited States15.0%	RURussia6.1%
Uranium extraction from seawater and wastewater	61	CNChina82.0%	FRFrance3.1%	USUnited States2.7%
Nuclear energy policy, economics and climate role	43	USUnited States24.7%	CACanada10.1%	GBUnited Kingdom9.5%
Nuclear waste immobilisation and storage	37	USUnited States29.2%	KRSouth Korea15.5%	CNChina14.5%

Share of each sub-area's papers in the top 10%. Source: OpenAlex, pulled 18 October 2026. Method

Earlier and recent

The same top 10%, split into 2021–2023 and 2024–2025.

FallingRising2021–20232024–2025Change

CNChina 40.1%46.9%+6.8 pts

USUnited States 24.9%19.0%−5.9 pts

KRSouth Korea 3.3%5.7%+2.4 pts

GBUnited Kingdom 4.0%2.1%−1.9 pts

RURussia 2.9%3.3%+0.5 pts

FRFrance 2.4%1.8%−0.7 pts

CACanada 2.9%1.2%−1.8 pts

INIndia 2.1%1.4%−0.6 pts

Greyed rows rest on fewer than five papers of credit in one period.

Share of the 10% most cited papers: 396 papers in 2021–2023, 352 in 2024–2025. Source: OpenAlex, pulled 18 October 2026. Method

2026 so far: a different count

Not the most cited papers: every 2026 paper matched so far (1,529), and a paper counts in full for each country on it. This year's papers are too new to rank by citations, so these shares cannot be compared with the ones above.

CNChina37.9%of 2026 papers have an author here
USUnited States17.8%of 2026 papers have an author here
KRSouth Korea7.3%of 2026 papers have an author here
FRFrance6.0%of 2026 papers have an author here
JPJapan4.9%of 2026 papers have an author here

Who cites the top papers

How much more often a country's top papers are cited from home than its size predicts. Expected is the country's share of all papers in the field; the bar is the excess, in percentage points. Home citers include authors citing their own earlier work.

HomeExpectedExcess

CNChina 75.1%30.4%+44.7

USUnited States 42.6%21.0%+21.6

KRSouth Korea 26.1%6.9%+19.2

RURussia 22.9%3.9%+19.0

Based on up to 100 of each country's most cited single-country papers in the top 10%. Source: OpenAlex, pulled 18 October 2026. Method

Behind the share

Institutions with the most credit

1CNXi'an Jiaotong University5.8%
2CNShanghai Jiao Tong University4.3%
3USIdaho National LaboratoryResearch facility4.1%
4CNTsinghua University2.3%
5USOak Ridge National LaboratoryResearch facility2.1%
6CNNuclear Power Institute of ChinaResearch facility2.1%
7CNChinese Academy of SciencesGovernment lab2.1%
8??State Key Laboratory of Multiphase Flow in Power EngineeringResearch facility1.9%
9USLos Alamos National LaboratoryResearch facility1.5%
10CNEast China University of Technology1.4%

Share of the top 10%. Institutions across all 45 technologies

Who does the work

Sector	All	CN	US	KR
Universities	65.2%	76.0%	52.7%	65.1%
Research facilities	26.2%	16.1%	44.9%	28.4%
Government labs	5.9%	6.3%	0.1%	0%
Companies	1.7%	1.3%	2.3%	6.6%

Share of credit by type of institution, overall and for the three leading countries.

Across borders

19.7% of the top 10% have authors in more than one country.

CNUSChina with United States17
GBUSUnited Kingdom with United States14
FRUSFrance with United States7
CAUSCanada with United States7
CNGBChina with United Kingdom7

Most frequent pairings, by number of shared papers.

The papers behind the numbers

The five most cited papers this definition catches. If one looks out of place, the definition needs work.

Japanese evaluated nuclear data library version 5: JENDL-5
Journal of Nuclear Science and Technology, 2023ATJP
462citations
Environmental degradation of structural materials in liquid lead- and lead-bismuth eutectic-cooled reactors
Progress in Materials Science, 2022BECNFRGBUS
425citations
Nuclear energy: A pathway towards mitigation of global warming
Progress in Nuclear Energy, 2021IN
357citations
Adsorption of uranium (VI) by metal-organic frameworks and covalent-organic frameworks from water
Coordination Chemistry Reviews, 2022CN
349citations
Molten salt for advanced energy applications: A review
Annals of Nuclear Energy, 2022US
346citations

How this technology is defined

A paper counts if its title or abstract matches the search below. Articles in core journals and proceedings only; retracted papers are excluded.

"nuclear reactor" OR "small modular reactor" OR "fast reactor" OR "molten salt reactor" OR "nuclear fuel" OR "pressurized water reactor"

and its main topic in OpenAlex is one of: Nuclear reactor physics and engineering; Nuclear Engineering Thermal-Hydraulics; Nuclear Materials and Properties; Radioactive element chemistry and processing; Molten salt chemistry and electrochemical processes; Nuclear materials and radiation effects; Nuclear and radioactivity studies; Heat Transfer and Boiling Studies. The topic check removes papers that only mention the technology.

Papers matched, 2021–2025: 7,458
In the top 10%: 748
In the top 1%: 77
Countries with credit: 64
Credit with no known country: 2.6%

Every one of the 915 most cited papers was checked for relevance; 42 were left out as not about nuclear fission power

The most cited of those left out:

Advanced porous adsorbents for radionuclides elimination208 citations
Comparative review of different influence factors on molten salt corrosion characteristics for thermal energy storage140 citations
Review of pool and flow boiling heat transfer enhancement through surface modification138 citations
A review of liquid metal high temperature heat pipes: Theoretical model, design, and application68 citations
Reduction of U(VI) on Chemically Reduced Montmorillonite and Surface Complexation Modeling of Adsorbed U(IV)57 citations
Simultaneous laser-induced fluorescence, particle image velocimetry and infrared thermography for the investigation of the flow and heat transfer characteristics of nucleating vapour bubbles55 citations
On the viscosity of molten salts and molten salt mixtures and its temperature dependence52 citations
Numerical simulation of heat pipes in different applications47 citations
A Review on Pool and Flow Boiling Enhancement Using Nanofluids: Nuclear Reactor Application47 citations
International perspectives on glass waste form development for low-level and intermediate-level radioactive waste47 citations
Solidification performance and mechanism of typical radioactive nuclear waste by geopolymers and geopolymer ceramics: A review46 citations
Depressurization of CO2 in a pipe: Effect of initial state on non-equilibrium two-phase flow40 citations

Definition version 0.5, pilot. It is a plain text file: copy it, change it, rerun it.

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